Use the eXact® Strip DPD-3 (Potassium Iodide) ReagentStrip in a 10 mL sample after adding eXact® Strip DPD-1. Move eXact® Strip DPD-3 with a back and forth motion in the sample for roughly 30 seconds at a gentle rate of around 2 moves per second, remove & discard the strip, allow approximately 2 minutes for full color development in the sample, and read the sample in your favorite meter.

The reading obtained is the total chlorine concentration, or total oxidizer concentration, in parts per million (ppm) or milligrams per Liter (mg/L).